[알고리즘] 이분탐색

def sort(x,start,end):
    if start>end:
        return False
    mid=(start+end)//2
    if(A[mid]==x):
        return True
    if(A[mid]<x):
        start=mid+1
        return sort(x, start, end)
    elif(A[mid]>x):
        end=mid-1
        return sort(x, start, end)